GRANITEVILLE - Charles Hay visited a doctor after being exposed to chlorine from the Jan. 6 train collision in Graniteville. But that didn't stop him from getting a second opinion.

Mr. Hay, who turns 50 today, became the first person Monday to get a free health screening from the South Carolina Department of Health and Environmental Control.

"I just hope they don't find anything," said Mr. Hay, who has experienced labored breathing and has used an asthma inhaler since breathing chlorine that leaked from a train tanker car and drifted across the small town.

Nine people were killed in the accident, which released an estimated 60 tons of chlorine gas, and more than 500 sought medical attention at the hospital or with a physician, according to state health officials.

But they say it's likely that many more people were exposed to the toxic gas. About 430 people have signed up for the department's free medical screenings, and medical professionals urge anyone who thinks he or she was exposed to do so.

"This is part of our public health mission," said Erik Svendsen, an environmental epidemiologist with the department.

As part of the screening, Mr. Hay answered detailed questions about his exposure to the gas, symptoms he has experienced since and his health history. He was asleep in his bed when the gas began to leak, just blocks from the crash site, Mr. Hay said.

The question-and-answer portion of the screening was followed by measurements of his heart rate and blood pressure.

Mr. Hay also spent 10 minutes blowing into a tubular instrument that turned his breath into a liquid.

The sample will show the acidity in Mr. Hay's lungs, a measure of possible chlorine damage, said Dr. Monty Fetterolf, the chairman of the University of South Carolina Aiken's chemistry and physics department, who volunteered to help with the screenings.

Mental health specialists also will be on hand during the screenings. Many residents have experienced increased levels of stress since the incident, which forced an estimated 5,400 people from their homes.

DHEC started interviewing people who sought medical attention soon after the crash and has visited Graniteville many times since.

"It became very clear that the picture we got early on is not really a picture of all the people who were affected by this train wreck," Dr. Svendsen said.

The focus of the current screenings is to make sure that people who need medical care get it, health professionals emphasized. However, here also is a push to conduct long-term studies of some people who were exposed to the gas.

Though there is extensive research into the effects of chlorine, Graniteville provides a unique opportunity to observe the effects in women and children, Dr. Svendsen said.

Health screenings will continue this week, including a full slate Saturday.

Reach Josh Gelinas at (803) 648-1395, ext. 110, or josh.gelinas@augustachronicle.com.